Mutations in the X-linked gene coding for the calcium-/calmodulin dependent serine protein kinase (CASK) are associated with severe neurological disorders ranging from intellectual disability (in males) to mental retardation and microcephaly with pontine and cerebellar hypoplasia (MICPCH). CASK is involved in transcription control, in the regulation of trafficking of the postsynaptic NMDA and AMPA receptors, and acts as a presynaptic scaffolding protein. For CASK missense mutations it is mostly unclear which of CASK's molecular interactions and cellular functions are altered and contribute to patient phenotypes. We identified five CASK missense mutations in male patients affected by neurodevelopmental disorders. These and five previously reported mutations were systematically analyzed with respect to interaction with CASK interaction partners by coexpression and coimmunoprecipitation. https://www.selleckchem.com/products/fx-909.html We show that one mutation in the L27 domain interferes with binding to Sap97. Two mutations in the guanylate kinase (GK) domain affect binding of CASK to the nuclear factors CINAP and Tbr1. A total of five mutations in GK as well as PDZ domains affect binding of CASK to the presynaptic cell adhesion molecule Neurexin. Upon expression in neurons, we observe that binding to Neurexin is not required for presynaptic localization of CASK. We show by bimolecular fluorescence complementation assay that Neurexin induces oligomerization of CASK, and that mutations in GK and PDZ domains interfere with the Neurexin-induced oligomerization of CASK. Our data are supported by molecular modelling, where we observe that the cooperative activity of PDZ, SH3 and GK domains is required for Neurexin binding and oligomerization of CASK.COVID-19, the ongoing pandemic caused by SARS-CoV2 is a major threat to the entire human race. It is reported that SARS-CoV2 seems to have relatively low pathogenicity and higher transmissibility than previously outbroke SARS-CoV. To explore the reason of increased transmissibility of SARS-CoV2 compared to SARS-CoV, we have performed a comparative analysis on the structural proteins (Spike, Envelope, Membrane, Nucleoprotein) of two viruses. Our analysis revealed that extensive substitutions of hydrophobic to polar and charged amino acids in spike glycoproteins of SARS-CoV2 creates an intrinsically disordered region (IDR)at the beginning of membrane-fusion subunit and intrinsically disordered residues in fusion peptide. IDR provides potential site for proteolysis by furin and enriched disordered residues facilitate prompt fusion of the SARS-CoV2 with host membrane by recruiting Molecular Recognition features. Here, we have hypothesized that mutation driven accumulation of intrinsically disordered residues in spike glycoproteins play dual role in enhancing viral transmissibility than previous SARS-corona virus. These analyses may help in epidemic surveillance and preventive measures against COVID-19. This article is protected by copyright. All rights reserved.Sorting nexins (SNXs) are a diverse group of cytoplasmic- and membrane-associated phosphoinositide-binding proteins containing the PX domain proteins. The function of SNX proteins in regulating intracellular protein trafficking consists of endocytosis, endosomal sorting, and endosomal signaling. Dysfunctions of SNX proteins are demonstrated to be involved in several cancerous/neoplastic diseases. Here, we review the accumulated evidence of the molecular structure and biological function of SNX proteins and discuss the regulatory role of SNX proteins in distinct cancerous/neoplastic diseases. SNX family proteins may be a valuable potential biomarker and therapeutic strategy for diagnostics and treatment of cancerous/neoplastic diseases.To investigate the impact of sampling patients on descriptive characteristics of physician patient-sharing networks.
Medicare claims data from 10 hospital referral regions (HRRs) in the United States in 2010.
We form a sampling frame consisting of the full cohort of patients (Medicare enrollees) with claims in the 2010 calendar year from the selected HRRs. For each sampling fraction, we form samples of patients from which a physician ("patient-sharing") network is constructed in which an edge between two physicians depicts that at least one patient in the sample encountered both of those physicians. The network is summarized using 18 network measures. For each network measure and sampling fraction, we compare the values determined from the sample and the full cohort of patients. Finally, we assess the sampling fraction that is needed to measure each network measure to specified levels of accuracy.
We utilized administrative claims from the traditional (fee-for-service) Medicare.
We found that measurhighly heterogeneous effect across different network measures on the extent to which sample-based network measures resemble those evaluated using the full cohort. Even random sampling of patients may yield physician networks that distort descriptive features of the network based on the full cohort, potentially resulting in biased results.Focal epilepsy (FE) is clinically highly heterogeneous. It has been shown recently that not only rare but also a subset of common genetic variants confer risk for FE. The relatively modest power of genetic studies in FE suggests a high genetic heterogeneity of FE when grouped as one disorder. We hypothesize that the clinical heterogeneity of FE is correlated with genetic heterogeneity on a common risk variant level. To test the hypothesis, we used an FE polygenic risk score "FE-PRS" that combines small effect sizes of thousands of common variants from the largest FE-GWAS (genome-wide association study) into a single measure. We grouped 414 individuals with FE according to common clinical features into subgroups, either by one feature at a time or by all features combined in a cluster analysis. We examined their association with FE-PRS compared to 20 435 matched population controls and observed heterogeneous FE-PRS burden among the subgroups. The highest phenotypic variance explained by FE-PRS was identified in a cluster analysis-defined FE subgroup where all individuals had unknown etiologies and psychiatric comorbidities, and the majority had early onset seizures. Our results indicate that genetic factors associated with FE have differential burden among FE subtypes. Future studies using better-powered FE-PRS might have clinical utility.